1. Field of the Invention
The present invention relates generally to electrical switching apparatus and, more particularly, to electrical switching apparatus including a terminal housing. The invention further relates to terminal housings for electrical switching apparatus.
2. Background Information
Circuit breakers for telecommunication systems are small in comparison with circuit breakers commonly associated with power distribution networks. By way of example, in accordance with one conventionally known telecommunication system circuit breaker design, the circuit breaker measures about 2.5 inches high by about 2.0 inches long by about 0.75 inch thick, when viewed with the operating handle extending horizontally and moving in a vertical arc. While having a reduced size, the telecommunication system circuit breaker must still accommodate the various components (e.g., separable contacts; trip mechanism; operating mechanism) associated with larger circuit breakers.
Electrical switching apparatus, such as the aforementioned circuit breakers, as well as transfer switches, network protectors and the like, are often equipped with auxiliary switches that provide signals indicating certain conditions within the apparatus. For example, such auxiliary switches indicate whether the separable contacts are open or closed and/or whether the device has been tripped open. The signals generated by the switches can be used for communicating the condition to a remote location.
Auxiliary switches are either mechanically actuated, usually through physical contact with, or by a linkage to, the operating mechanism that opens and closes the separable contacts, or are of a non-contact variety being actuated by any known or suitable non-contact sensor (e.g., without limitation, Hall effect device; proximity sensor; optical sensor). However, some non-contact auxiliary switch designs are more complex thus undesirably increasing the complexity and associated cost of the circuit breaker.
The space constraints associated with small electrical switching apparatus pose a still further difficulty with respect to where and how to locate the terminals that receive signals from the auxiliary switch and the conductors which electrically connect such terminals to the auxiliary switch in order to output the signals. Specifically, although it is sometimes desirable to position the auxiliary switch terminals proximate the line and load terminals of the electrical switching apparatus, space at this location is extremely limited due to the small physical size of the apparatus. Moreover, telecommunication system circuit breakers, for example, are typically mounted in a relatively tight configuration within a multi-level rack where the small size and extended length of the circuit breakers make it difficult to reach behind the circuit breaker to install (i.e., electrically connect) it within the rack or other suitable enclosure.
Thus, there is a need for an improved auxiliary switch terminal arrangement for use with small electrical switching apparatus, such as telecommunication system circuit breakers.
There is, therefore, room for improvement in electrical switching apparatus including auxiliary switches, and in the arrangement of auxiliary switch conductors and terminals.
There is further room for improvement in circuit breakers, such as telecommunication system circuit breakers, having a reduced size but including an auxiliary switch disposed within the housing of the circuit breaker, and auxiliary switch terminals disposed proximate the line and load terminals of the circuit breaker.